With all the talk about designing for responsive websites, two little words keep cropping up – em and rem. But what are they?
Em and rem, along with pixels, are units and methods to measure and resize type. Em and rem are relative, rather than static, units and are being used more and more for responsive web design schemes. Let’s dive into this concept today and explain things a little more clearly!
Where Did Ems Come From?
Ironically enough the term “em” originates with print design. An em is the size of an uppercase M in any typeface, making the size relative to the font.
Many print designers are familiar with em (and their counterpart en) when it comes to spacing. An em space or en space – which is the size of an uppercase N – is often used to make words and spaces look better in big type. The same is true of em and en dashes – or the long and short dash.